Simon Cowell has offered a £63million deal, spread over 21 years, to the married socialite who is expecting their child, sources close to the TV tycoon revealed yesterday.

Simon Cowell has pledged to support his child with £63million spread over 21 years

The child support payments of £3million-a-year would continue until the unborn baby reaches the legal age of adulthood in America, according to a legal expert with intimate knowledge of the case.

He revealed that Cowell, 53, is also offering a “job for life” to his pregnant mistress Lauren Silverman, 36, which is most likely to be “property manager” of his mansions and estates in the US and Britain.

The X Factor supremo has been cited in court papers filed in New York by Mrs Silverman’s husband Andrew, 37, who was one of his closest friends. Mr Silverman is suing his wife for divorce on the grounds of adultery. As well as demanding sole custody of their seven-year-old son Adam, Mr Silverman is asking a Manhattan Supreme Court judge to agree to enforce a prenuptial agreement his wife signed before they married that is reportedly “very much less than generous”.

Cowell has hired top Los Angeles entertainment attorney Marty Singer to try to avoid the humiliation of having to appear in court and be questioned about his private life as well as taking a DNA paternity test.

A senior legal source told the Sunday Express: “Simon isn’t going to dispute that he is the father but the last thing he wants is for his name and reputation to be publicly dragged through the dirt.

“The truth is, he doesn’t yet know whether he will end up marrying Lauren somewhere down the line in years to come but, in the meantime, he wants to ensure he does the right thing for her and their baby as well as resolving this mess.”

Money represents no real object to jet-setter Cowell, who is estimated by financial magazine Forbes to be earning in excess of £60million a year from X Factor and his other TV talent shows in the US and UK.

The source added that Cowell has “happily agreed” to cover all of Mr Silverman’s legal costs, which could amount to as much as £200,000, if he drops the adultery claim and accepts a simple “no contest” divorce.

Mr Silverman, a property tycoon, was last night said to be “mulling over his options” despite the fact that his brother Alexander has described Mrs Silverman’s affair with Cowell as “the ultimate act of betrayal”.

Yesterday, both warring husband and wife were still sharing the £2.8million mansion they bought together four years ago in The Hamptons, an exclusive enclave of upstate New York.

At one stage, Mr Silverman roared off in a silver Mercedes without stopping to talk to waiting reporters.

His wife, said to be 10 weeks pregnant by Cowell, stayed indoors most of the time, emerging only briefly to be driven away by friends.

Meanwhile, in Los Angeles, where Cowell owns estates in Beverly Hills and Hollywood Hills, the X Factor boss was keeping a low-profile after fobbing off journalists earlier in the week by declaring “I haven’t read the newspapers yet,” at a Fox press conference about his show’s third season, which starts airing next month.

Privately, he is said to be “angry and perplexed” about publicity over his affair with Mrs Silverman, especially photos that surfaced on the US website TMZ showing the couple kissing on his £2million-a-month luxury charter yacht in the Caribbean.

The pictures are believed to have been taken last summer when Mrs Silverman and her husband, then still a close friend of Cowell, joined him on holiday at the millionaires’ Sandy Lane resort in Barbados.

Lauren Silverman and her husband Andrew are set to divorce following the baby revelation

Simon isn’t going to dispute that he is the father but the last thing he wants is for his name and reputation to be publicly dragged through the dirt

A senior legal source

The couple had known Cowell for at least seven years but the X Factor boss’s affair with Mrs Silverman reportedly began as long as two years ago.

She is said to be hoping that Cowell, whether or not they stay together, would give her a TV reality show like the Kardashians but sources close to him say there is “no way” he would contemplate that with his reputation already on the line.

A workaholic who sleeps for only four hours a night, Simon in the past has confessed: “I’m content but not fulfilled yet. I can always do more.”

It was presumed this was a reference to his views on business but could have been linked to a desire to start a family.

He is close to his mother Julie, who is said to be thrilled by the news that she will have a new grandchild.

One source who has known Simon since the Nineties said: “He will be a great father. Simon is so playful and is naturally spirited. He’s been so busy aiming for other successes in his life he didn’t think fatherhood would be for him.

“And he will be happy to have a baby while his mum is here. It may not be ideal circumstances but it’s the time in his life that it’s now or never.”

The source added: “At the back of his mind, having kids is like a last-minute Christmas panic buy and I’m sure for a man who can afford everything in the shop he’s scooped up a family now.

“No one expected Elton John and David Furnish to have a family but since having two boys in recent years the couple have never been happier.”

Cowell has lavished attention on his friends’ children, including ex-girlfriend Sinitta’s adopted son and daughter.

Last year, Sinitta said: “He is so good with my children and they adore spending time with him. He has a way of being very natural and funny with them. We all enjoy the days when we can get together.”